pinctrl: sh-pfc: r8a7778: Fix duplicate SDSELF_B and SD1_CLK_B

The FN_SDSELF_B and FN_SD1_CLK_B enum IDs are used twice, which means
one set of users must be wrong.  Replace them by the correct enum IDs.

Fixes: 87f8c988

 ("sh-pfc: Add r8a7778 pinmux support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20191218194812.12741-2-geert+renesas@glider.be